abstract class Person{
  String name='';
  int get age => 18;
  void run();
}

class Student implements Person{
  @override
  String name='';
  @override
  int get age => 15;
  @override
  void run(){
    print('Stop');
  }
}

void main(){
  var student = new Student();
  print(student.name);
  print(student.age);
  student.run();
}
